Current technologies for measuring at least one physical characteristic of an internally threaded surface, such as the shape of a thread form, include the casting or rubber replicating process, such as by Reporubber®, as illustrated in FIG. 14. The Reporubber® material is applied over several threads, allowed to cure, and is then removed. The material maintains its shape when removed. The resulting thread mold is sliced on-axis and placed on an optical comparator, where it is magnified. An overlay of the theoretical shape may be used to detect problem areas. This is a time consuming process and relies on the operator to perform the comparison, which can be subjective and requires a “trained eye.”
Another current approach is to use a mechanical stylus to trace the thread form, such as with the use of a contour measuring system, as illustrated in FIG. 15. This method is time-consuming to setup and collect data. It is also fragile.
Accordingly, there exists a need for improved internal thread measurement systems.